The present invention relates to a door locking system for a motor vehicle.
Door locking systems for motor vehicles with and without central lock function are known. To check on whether a vehicle is in fact properly locked, including all doors and hatches after being locked, the user must either rely on the position of the lock pins on the doors and manually check the locking of the trunk, or manually check all doors and the trunk in one inspection operation around the vehicle. A manual check by the user is a problem, in particular in systems having a so-called electronic lock. Such systems function automatically and automatically initiate an opening procedure as soon as the user (i.e., the key) is at a specified distance from the vehicle so that either the vehicle is unlocked in a fully automatic process or preparations are made for an unlocking operation and the vehicle is automatically unlocked as soon as the user operates an opening handle (see for example German Patent DE 199 42 485 A1). Conversely, the vehicle is automatically locked as soon as the key is beyond the specified distance range from the vehicle. A manual check of the lock positions by the user would thus be very tedious, and would in fact be possible only if the user is not carrying the vehicle key with him.
Furthermore, a door lock for a motor vehicle is disclosed in German Patent DE 101 55 836 A1. With this door lock the open position of the locking element is monitored. A contact switch is provided for this purpose, monitoring the open position of the locking element and generating a signal as soon as this open position has been reached, the signal being used by a control unit to interrupt the power supply to the drive motor of the locking element. This prevents the drive motor from running on block and being burdened unnecessarily.
The present invention provides a door locking system for a motor vehicle that is improved with regard to comfort and safety.
According to the present invention, this object is achieved by a locking element that can be operated for opening or locking via an actuator; a control unit for triggering the actuator; and a position monitoring means for detecting a lock position of the at least one locking element, and which is assigned to at least one locking element, wherein each position monitoring means cooperates with a control means for checking on whether a proper locked state prevails such that a setpoint state and actual state of the at least one locking element are comparable and an acknowledgement signal can be generated when the states do not match. Such a door locking system includes an actuator in the form of an electric or hydraulic drive or the like for opening and/or locking a locking element, a control unit (e.g., a separate door controller or a central engine controller) for triggering the actuator and position monitoring means (e.g., photoelectric barrier, proximity sensor or a position sensor) for position monitoring of the locking element. This system also includes control means for checking on whether a proper locked state has been achieved. In this way, the setpoint and actual conditions of the locking elements are compared so that if the states do not correspond, an acknowledgement signal is generated. This acknowledgement signal may be used either for triggering a signal generator such as a horn or headlight or the like or it may serve as an intermediate signal for generating a triggering signal for a signal generator.
The control means are preferably designed as part of door controller or a central controller. Both the locking commands and the opening commands by means of which the corresponding setpoint status of the locking elements is defined is sent to these controllers as is the locking state detected by the position monitoring means by which the particular actual state of the locking elements is defined. According to this invention, the control means are designed so that they detect an improper locking state (not locked despite a locking command having been issued) on the basis of a deviation between the setpoint and actual states and then generate an acknowledgment signal. To generate an acknowledgment signal, for example, light sources (headlights, flashing lights, rear lights, interior lights, . . . ) or acoustic sources (horn) of the vehicle are triggered in a suitable manner by a certain signal pattern.
The position monitoring may be performed in various ways. In a first possible embodiment, the position monitoring is implemented via sensors, where the sensors detect the actual position of the locking means. In a second possible embodiment of this invention, the position monitoring is implemented by analyzing internal data within the controller. For example, the self-diagnosis within the controller triggering the actuators and/or the corresponding separately designed control means or control means integrated into a controller may be used for this purpose. In particular, the typical current characteristic of the startup current and/or running current and/or square-wave current of the actuator designed as an electric motor is performed. The actual position of the locking elements or actuators is not detected in this way. Instead, the instantaneous position of the locking elements is deduced on the basis of a check of boundary conditions.
Finally, the position monitoring and function monitoring may also be performed in particular by a combination of sensor monitoring and software monitoring.
In one aspect of the present invention, a locked state detected as not the proper state is also stored in the vehicle's onboard electronics and/or in the vehicle key. In this way, the user can at any time ascertain via the onboard computer which locking element has not locked properly and is therefore possibly defective. Secondly, the user, although already at a distance from the vehicle, may at any time determine on the basis of an inquiry by his key whether his vehicle has been properly locked. To this end, the key may be queried by depressing a certain button and the information displayed by an LED lighting up (green=properly locked, red=not properly locked).
The inventive door locking system can be used in systems having a central locking function.
With a door locking system designed according to this invention, the user receives an acknowledgment after locking is completed and/or after a locking procedure is concluded, indicating whether or not the vehicle is in fact properly locked and secured. If the vehicle is not properly locked despite the locking procedure having been initiated because, for example, an actuator in the form of an electric motor for driving a locking means is defective, for example, or is simply jammed, reference is made to this situation through suitable measures such as light signals and/or horn signals. A vibrating signal on the key is also conceivable as an acknowledgment signal. This is advantageous in particular when the user has assumed despite a light warning and/or acoustic warning that his vehicle has been properly locked. This vibrating signal may advantageously be initiated with a certain time lag whenever it is not suppressed by an acknowledgement (e.g., depressing a button) on the part of the user after a locking command has been issued.